349 
Centrifugal Force tipon the Cell. 
probably lighter than those displaced, or they may have been 
situated in a firmer part of the primordial utricle. Only 
a relatively small number of oil-globules are carried along 
with the chloroplasts ; usually they lie scattered in the more 
proximal portion of the filament left colourless by the removal 
of the chlorophyll. They are, of course, most numerous just 
back of the chlorophyll. Consequently, the end of the fila- 
ment presents a dark-green colour, which shades over gradually 
into the nearly colourless part from which the chlorophyll has 
been removed. 
Certain large oil-globules, in which are included one or 
more chlorophyll-grains, are carried along with the displaced 
mass. These larger oil-bodies doubtless arise from a fusion 
of smaller ones and the chloroplasts lying in contact with 
them. 
It sometimes happens that several such globules, together 
with other inclusions of the protoplasm, collect at certain 
points in the filament and form a sort of plug, which com- 
pletely prevents further movement at these places, where 
the contents will then accumulate as in the end of the 
filament. In several instances it was observed that those 
parts of the filament which were clogged in this way became 
injured and were cut off from the main portions by transverse 
walls, just as when any part is injured by crushing or 
otherwise. 
Twenty-four hours after displacement, considerable progress 
in the redistribution of the contents is noticeable, and in a few 
days there is nothing to indicate that any disturbance had 
taken place in those filaments which received no injury 
through clogging or otherwise. The oil-masses with their 
included chloroplasts redistribute themselves more slowly. 
Many of them soon disappear, probably by breaking up, 
thereby liberating the chloroplasts, when the oil doubtless 
takes part in the processes of metabolism ; others, however, 
persist for a longer time. 
A redistribution of the chloroplasts throughout the entire 
portion of the filament left nearly colourless by the displace- 
